GENERATOR “OF THE SEA”

GENERATOR Who has not experienced the beneficial effects of the measuring noise of the rain forests, the sea… the sound relaxes and soothes. That is why the simulator of the surf, which we offer to readers, is used as a stimulant of sleep in insomnia. Generator “of the sea” is easy to manufacture and configure, does not contain scarce radio parts and accessible even for novice radio Amateurs. Here’s how it works.

SOUND AND LIGHT TEAM

SOUND AND LIGHT TEAMAutomatic devices that produce sound and light signals, are widely used in various designs and models. Usually auto-switch performs the multivibrator, the control of sound or light emitter (call, dynamic head, incandescent, etc.). These devices contain more transistors and a dozen resistors and capacitors.

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SIMPLE FREQUENCY COUNTER

A diagram of the frequency to control the frequencies in a relatively narrow range offers the magazine “Radio Fernsehen Elektronik” of the GDR. It contains all 7 elements. The device operates as follows. By using a series connected resistor R1 and Zener diode V1 of the input sinusoidal signal is converted into a rectangular amplitude Read more…

COMBINATION LOCK

COMBINATION LOCKAbout code locks wrote more than once. However, most of them are difficult to repeat. Design suggested by our Bulgarian friends (the journal “Radio Television Electronics”), devoid of this shortcoming. For opening this lock simply insert the key and complete the circuit with the resistor R1 a certain value (it is mounted in the housing of the key). If the resistance will be different from that specified on the schematic, the relay does not work and the lock will not unlock.

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NEW OLD COIL RUHMKORFF

NEW OLD RUHMKORFF'S COILInduction coil, in the last century invented Rumkorem, and is now used in experiments in physics. But now it is not fully satisfy the requirements of physical experiment creates interference, does not regulate the high voltage. consumes battery power, and feed the coil directly from the mains AC is impossible. We offer you to equip physical classrooms modernized version of the instrument developed on the basis of electronics.

ROTATES FIELD

ROTATE FIELDIn a previous article under the heading “electronics for beginners” (see “M-K” № 8, 1979) we understand how magnetic field is formed it Turned out that, in particular, generates supplied to the coil (solenoid) electric current. The same field with a certain force acts on it carried to the magnet. But the magnet with the same force acts on the wire, which carries current. On the phenomenon of the interaction of electric current and magnet based electric motors (electric motors).

OBJECTIVE EXAMINER

OBJECTIVE EXAMINERIn the sixth issue of our magazine in 1974 we told about the device “Pulse” for the control of knowledge of students. Practice operating the machine created by the participants NTTM Donetsk Polytechnic Institute, as well as the feedback from readers has convinced authors of the need to improve the design.

TRANSFORMERLESS INCLUSION OF LDS

TRANSFORMERLESS INCLUSION OF THE LDS10 years — 15 ago, the industry was widely released table lamps with fluorescent lamps, designed for a voltage of 127 V. A today 127 V network was preserved only in rare homes. It is clear that the owners of these lamps was now “tied” to expensive and bulky step-down transformers. We offer our readers we developed and tested a device that allows you to include a 127-volt lamp in the network a voltage of 220 V without the step-down transformer.

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